.\"
.\" Copyright (c) 2011-2024 Craig Small <csmall@dropbear.xyz>
.\" Copyright (c) 2011-2012 Sami Kerola <kerolasa@iki.fi>
.\" Copyright (c) 2002-2006 Albert Cahalan
.\"
.\" This program is free software; you can redistribute it and/or modify
.\" it under the terms of the GNU General Public License as published by
.\" the Free Software Foundation; either version 2 of the License, or
.\" (at your option) any later version.
.\"
.\"
.TH SKILL 1 2024-08-01 procps-ng
.SH NAME
skill, snice \- send a signal or report process status
.SH SYNOPSIS
.B skill
.RI [ signal-option ]
.RI [ other-option " .\|.\|.\&]"
.I expression
.P
.B snice
.RI [ new-priority ]
.RI [ option " .\|.\|.\&]"
.I expression
.SH DESCRIPTION
These tools are obsolete and unportable.  The command syntax is
poorly defined.  Consider using the
.BR killall ,
.BR pkill ,
and
.B pgrep
commands instead.
.PP
The default signal for \fBskill\fP is TERM.  Use \fB\-l\fP or \fB\-L\fP to list
available signals.  Particularly useful signals include HUP, INT,
KILL, STOP, CONT, and 0.  Alternate signals may be specified in three
ways: \fB\-9\fP \fB\-SIGKILL\fP \fB\-KILL\fP.
.PP
The default priority for \fBsnice\fP is +4.  Priority numbers range from
+20 (slowest) to \-20 (fastest).  Negative priority numbers are
restricted to administrative users.
.SH OPTIONS
.TP
.BR \-f , \ \-\-fast
Fast mode.  This option has not been implemented.
.TP
.BR \-i , \ \-\-interactive
Interactive use.  You will be asked to approve each action.
.TP
.BR \-l , \ \-\-list
List all signal names.
.TP
.BR \-L , \ \-\-table
List all signal names in a nice table.
.TP
.BR \-n , \ \-\-no\-action
No action; perform a simulation of events that would occur but do not
actually change the system.
.TP
.BR \-v , \ \-\-verbose
Verbose; explain what is being done.
.TP
.BR \-w , \ \-\-warnings
Enable warnings.  This option has not been implemented.
.TP
.BR \-h , \ \-\-help
Display help text and exit.
.TP
.BR \-V , \ \-\-version
Display version information.
.SH "PROCESS SELECTION OPTIONS"
Selection criteria can be: terminal, user, pid, command.  The options
below may be used to ensure correct interpretation.
.TP
.BI \-t \ tty\fR,\  \-\-tty \ tty
The next expression is a terminal (tty or pty).
.TP
.BI \-u \ user\fR,\  \-\-user \ user
The next expression is a username.
.TP
.BI \-p \ pid\fR,\  \-\-pid \ pid
The next expression is a process ID number.
.TP
.BI \-c \ command\fR,\  \-\-command \ command
The next expression is a command name.
.TP
.BI \-\-ns \ pid
Match the processes that belong to the same namespace as pid.
.TP
.RI \fB\-\-nslist \ ns , .\|.\|.
list which namespaces will be considered for the \fB\-\-ns\fP option.
Available namespaces: ipc, mnt, net, pid, user, uts.
.SH SIGNALS
The behavior of signals is explained in
.BR signal (7)
manual page.
.SH EXAMPLES
.TP
.B snice \-c seti \-c crack +7
Slow down \fBseti\fP and \fBcrack\fP commands.
.TP
.B skill \-KILL \-t /dev/pts/*
Kill users on PTY devices.
.TP
.B skill \-STOP \-u viro \-u lm \-u davem
Stop three users.
.SH "SEE ALSO"
.BR kill (1),
.BR kill (2),
.BR killall (1),
.BR nice (1),
.BR pkill (1),
.BR renice (1),
.BR signal (7)
.SH STANDARDS
No standards apply.
.SH AUTHOR
.MT albert@users.sf.net
Albert Cahalan
.ME
wrote skill and snice in 1999 as a replacement for a non-free
version.
.SH "REPORTING BUGS"
Please send bug reports to
.MT procps@freelists.org
.ME .
